Buggy code:
public abstract class Expression extends Statement { public static final boolean isConstantValueRepresentable ( Constant constant , int constantTypeID , int targetTypeID ) { } public Constant constant ; public int implicitConversion ; public TypeBinding resolvedType ; public Expression ( ) { } public FlowInfo analyseCode ( BlockScope currentScope , FlowContext flowContext , FlowInfo flowInfo ) { } public FlowInfo analyseCode ( BlockScope currentScope , FlowContext flowContext , FlowInfo flowInfo , boolean valueRequired ) { } public final boolean checkCastTypesCompatibility ( Scope scope , TypeBinding castType , TypeBinding expressionType , Expression expression ) { if ( ( castType == null ) || ( expressionType == null ) ) return true ; boolean use15specifics = ( scope . compilerOptions ( ) . sourceLevel ) >= ( JDK1_5 ) ; if ( castType . isBaseType ( ) ) { if ( expressionType . isBaseType ( ) ) { if ( expressionType == castType ) { if ( expression != null ) { this . constant = expression . constant ; } tagAsUnnecessaryCast ( scope , castType ) ; return true ; } boolean necessary = false ; if ( ( expressionType . isCompatibleWith ( castType ) ) || ( necessary = BaseTypeBinding . isNarrowing ( castType . id , expressionType . id ) ) ) { if ( expression != null ) { expression . implicitConversion = ( ( castType . id ) << 4 ) + ( expressionType . id ) ; if ( ( expression . constant ) != ( Constant . NotAConstant ) ) { constant = expression . constant . castTo ( expression . implicitConversion ) ; } } if ( ! necessary ) tagAsUnnecessaryCast ( scope , castType ) ; return true ; } } else if ( use15specifics && ( scope . environment ( ) . computeBoxingType ( expressionType ) . isCompatibleWith ( castType ) ) ) { tagAsUnnecessaryCast ( scope , castType ) ; return true ; } return false ; } else if ( ( use15specifics && ( expressionType . isBaseType ( ) ) ) && ( scope . environment ( ) . computeBoxingType ( expressionType ) . isCompatibleWith ( castType ) ) ) { tagAsUnnecessaryCast ( scope , castType ) ; return true ; } switch ( expressionType . kind ( ) ) { case Binding . BASE_TYPE : if ( expressionType == ( NullBinding ) ) { tagAsUnnecessaryCast ( scope , castType ) ; return true ; } return false ; case Binding . ARRAY_TYPE : if ( castType == expressionType ) { tagAsUnnecessaryCast ( scope , castType ) ; return true ; } switch ( castType . kind ( ) ) { case Binding . ARRAY_TYPE : TypeBinding castElementType = ( ( ArrayBinding ) ( castType ) ) . elementsType ( ) ; TypeBinding exprElementType = ( ( ArrayBinding ) ( expressionType ) ) . elementsType ( ) ; if ( ( exprElementType . isBaseType ( ) ) || ( castElementType . isBaseType ( ) ) ) { if ( castElementType == exprElementType ) { tagAsNeedCheckCast ( ) ; return true ; } return false ; } <START_BUG> return checkCastTypesCompatibility ( scope , ( ( ArrayBinding ) ( castType ) ) . elementsType ( ) , exprElementType , expression ) ; <END_BUG> case Binding . TYPE_PARAMETER : if ( expressionType instanceof ReferenceBinding ) { ReferenceBinding match = ( ( ReferenceBinding ) ( expressionType ) ) . findSuperTypeErasingTo ( ( ( ReferenceBinding ) ( castType ) ) ) ; if ( match == null ) { checkUnsafeCast ( scope , castType , expressionType , match , true ) ; } } else { checkUnsafeCast ( scope , castType , expressionType , null , true ) ; } return checkCastTypesCompatibility ( scope , ( ( TypeVariableBinding ) ( castType ) ) . upperBound ( ) , expressionType , expression ) ; default : switch ( castType . id ) { case TypeIds . T_JavaLangCloneable : case TypeIds . T_JavaIoSerializable : tagAsNeedCheckCast ( ) ; return true ; case TypeIds . T_JavaLangObject : tagAsUnnecessaryCast ( scope , castType ) ; return true ; default : return false ; } } case Binding . TYPE_PARAMETER : case Binding . WILDCARD_TYPE : if ( castType instanceof ReferenceBinding ) { TypeBinding match = ( ( ReferenceBinding ) ( expressionType ) ) . findSuperTypeErasingTo ( ( ( ReferenceBinding ) ( castType ) ) ) ; if ( match != null ) { tagAsUnnecessaryCast ( scope , castType ) ; return true ; } } return checkCastTypesCompatibility ( scope , castType , ( ( TypeVariableBinding ) ( expressionType ) ) . upperBound ( ) , expression ) ; default : if ( expressionType . isInterface ( ) ) { switch ( castType . kind ( ) ) { case Binding . ARRAY_TYPE : switch ( expressionType . id ) { case TypeIds . T_JavaLangCloneable : case TypeIds . T_JavaIoSerializable : tagAsNeedCheckCast ( ) ; return true ; default : return false ; } case Binding . TYPE_PARAMETER : TypeBinding match = ( ( ReferenceBinding ) ( expressionType ) ) . findSuperTypeErasingTo ( ( ( ReferenceBinding ) ( castType ) ) ) ; if ( match == null ) { checkUnsafeCast ( scope , castType , expressionType , match , true ) ; } return checkCastTypesCompatibility ( scope , ( ( TypeVariableBinding ) ( castType ) ) . upperBound ( ) , expressionType , expression ) ; default : if ( castType . isInterface ( ) ) { ReferenceBinding interfaceType = ( ( ReferenceBinding ) ( expressionType ) ) ; match = interfaceType . findSuperTypeErasingTo ( ( ( ReferenceBinding ) ( castType . erasure ( ) ) ) ) ; if ( match != null ) { return checkUnsafeCast ( scope , castType , interfaceType , match , false ) ; } tagAsNeedCheckCast ( ) ; match = ( ( ReferenceBinding ) ( castType ) ) . findSuperTypeErasingTo ( ( ( ReferenceBinding ) ( interfaceType . erasure ( ) ) ) ) ;

Fix:
return checkCastTypesCompatibility ( scope , castElementType , exprElementType , expression ) ;